Adaptor plate for tow bars



May 4, 1948. H. RUSSELL ADAPTOR PLATE FOR TOW BARS 2 Sheets-Sheet 1 Filed on. 2a, 1946 IN VEN TOR.

uJJe/Z Mm A TTORNE Y ay 4, 1948. B. H. RUSSELL I 2,440,377

' F0 BARS INVEN TOR.

ATTORNEY Patented May 4, 1948 PATENT GFFl-CE Boyd 1!. Russell, Oaro, Mich. Application October 28, 13,46, Serial N o. '7 06,145

6 Claims.

hi nv n io rela es to adapt r plates for tow bars for coupling or looking motor vehicles together by enga ement the bump thereoi.

one of the prime objects oi the invention is to desi n a a aptor p ate whi h, whe -am i t o t rms an xten on of meter-clamps. so that the tow :bar may be utilized to en mp rs f various sizes and shapes. so-that one vehicle m y be coupled to another vehicle :for towing at any reasonable speed and thereby eliminate the necessity of providing a driver for the towed vehicle.

Another ohlect is to provide a very simple, pra cal a d inexpensive adaptor plate .can be easily and quickly attached to and centered on a tow bar, so that the towed vehicle will he held in direct alignment with the towin vehicle, said assembly compensating for variations caused by unevenness .of roadways, turning mov ment of the towing vehicle, or contact oi the vehicle wheels with raised obstacles .or other read irregularities.

A further object still is to design an adaptor plate which can be easily andnnickly attached and/tor detached, and hich requires no additional securing means for securing it in position on the clamp.

With the above and other objects in view, the present invention consists in the combination and arrangement of parts, hereinafter more fully described, illustrated in the accompanying drawings, and more particularly described in the appended claims, it being understood that changes may be made in the form, size, proportion, and minor details of construction, without departing from the spirit, or sacrificing any of the advantages oi the invention.

In the drawings:

Fig. 1 is a side-elevational view illustrating the application of the invention for towing purposes.

Fig. 2 is an enlarged, side-elevational view of the tow bar showing my adaptor plate in position thereon, and clamped to a bumper, the broken lines illustrating the swiveling action of the tow bar.

Fig. 3 is an enlarged, longitudinal sectional view through the adaptor plate.

Fig. 4 is a sectional plan view taken on the line 4-4 of Fig. 2 and looking in the direction indicated by the arrows.

Fig. 5 is an inverted plan view showing the flanges and rib on the clamp.

The instant invention relates to adaptor plates applicable to tow bars of all kinds so that the clamp-assemblies which are readily reversible, may be lengthened to accommodate bumpers of various sizes, cross sectional shapes and curvatures.

Referring now to the drawings. The letters l3 and C indicate the towing vehicle and a towed vehicle respectively, the towing vehicle being equipped with a special rear bumper 6, and the towed vehicle also has a similar design bumper 1 shaped as clearly shown in Fig. l of thedrawmgs.

The two bar structure shown in the instant application conforms generally to the structure shown in Patent No. 2,243,347 grant-ed to Cletus A. Klein and myself, May 27, 1941, and readily fits conventional bumpers of uniform size and shape, but due to changes in bumper design, I find it necessary, in order to accommodate the new sites and shapes, to increase the throat size and clamping range of the clamp assemblies, and I have, therefore, provided an adaptor plate A which is attachable to and form-s an extension of the clamp, "so that bumpers of any irregular cross-sectional shape and size may be engaged.

The tow bar 8 includes clamp assemblies E andrespectively, provided on the opposite ends thereof, these assemblies being of substantially the same design, and the operation is identical, excepting that the assembly is mounted for universal movement, a socket 9 being provided in one leg Ill of the clamp H, and accommodates a ball bolt l2 provided on the one end of the draw bar, a plate l4 being fitted over said ball, and bolts 15 serve to secure the plate in position.

A horizontally disposed jaw member I6 is pivotally secured to the one end of the clamp H by means of a bolt l'l, said member being formed with spaced-apart jaws It! to suit various size bumpers, and a similar horizontally disposed jaw I9 is provided on the leg 20 of the clamp ll.

Inasmuch as the bumpers 6 and I are irregular in cross section and as shown in Fig. 2 of the drawings, I rotate the assembly E so that the clamp II is located at the top and the adaptor plate A is mounted thereon in inverted position, vertically aligned openings 2| being provided in the jaw sections l6 and 20 and accommodate a bolt 22 so that the jaws may be drawn towards each other to clamp the assembly to a bumper.

The clamp II is angular in shape, the flanges 23 being cast integral with the section III, and

a centrally disposed rib 24 i provided on the lower edge of the clamp (see Fig. and for a purpose to be presently described.

The adaptor plate A is formed as clearly shown in Figs. 3 and 4 of the drawings; it comprises a rectangular shaped, preferably cast frame A which includes spaced apart parallel curved side bars 25, the rear ends of which are connected by a back bar 26 which depend below the side bars, and which is provided with a pocket 21 intermediate its length to accommodate the rib 24, this back bar 26 bearing against the lower rear edge of the clamp H with the rib 24 seated in the pocket 27 and serving to center the adaptor 1 plate on the clamp assembly.

A transversely disposed rib 28 serves to coin nect the side bars at a point spaced from the front end of the plate, the front ends of said side bars having jaws 29 cast integral therewith for engaging the edges of the bumper 1.

Notched seats 3i are provided in the lower face of the parallel side bars 25 and are shaped to seat and accommodate the jaw l9 of the clamp H, the outer edge of each pocket 2-! being closed to prevent sidewise movement of the plate thereon.

The adaptor can be easily and quickly applied; it requires no bolts or other securing means; it is merely necessary to tilt theadaptor plate A so that the leg 20 of the the pocket 27, with the ends of the side bars 25 hearing against the flanges 23 of the clamp H, with the jaw l9 accommodated in the notched seats 3| provided in the side bars of the adaptor plate, and the operation of the device is then the same as described in the patent herein referred to.

The clamp assembly E, due to its universalv clamp H passes throughquickly applied and enables! "adaptor plate to accommodate the teeth of one of said jaw sections.

Ly obvious that I have perfected a very simpl practical and convenient adaptor plate for us on automobile tow bars and the like.

What I claim is:

1. The combination with a tow bar forme with an angularly shaped clamp including a jav section, a similar jaw section pivotally connectec to said clamp, of an adaptor plate detachably mounted on one. of said jaw sections and forming asubstantially horizontal extension thereof, wit its rear section bearing against the rear edge of said jaw, and means for securing the jaws and plate to a vehicle bumper.

2. The combination as defined in claim 1 in whichseats are provided in the lower face of the 3. The. combination set forth in claim 1 in which a centrally disposed seat is provided on the rear section of the adaptor plate to accommodate a rib on the clamp and to center the plate on one of the jaw sections.

4. The combination as defined in claim 1 in which the clamp is formed with a centrally disp'osed rib and an extending jaw section, the adaptor plate comprising a rectangular frame formed with spaced-apart side bars, front and rear bar sections connecting seats in the rear bar and side bars to accommodatethe rib and jaw sections respectively of the clamp.

5. An adaptor plate for automobile tow bars comprising a rectangular-shaped frame terminating in an upturned jaw section, the rear bar section of said frame depending below the side bars and being formed with a rib accommodating pocket therein, and notches provided in the lower face of the side bars at points intermediate their length.

'6. The combination with a clamping jaw, of a vehicle tow bar comprising, a substantially rectangular-shaped adaptor plate adapted to fit over the jaw section of the clamp and form an extension thereof, the rear end of said plate bearing against the rear lower face of the clamp, 

